The deoxyglucose method is being applied to the monkey to advance knowledge regarding the parts of the brain which are involved in the processing of visual information. By measuring rates of local cerebral glucose utilization in animals during their performance of tasks involving different types of visual stimuli we anticipate learning which parts of brain are involved in such functions as discrimination, memory and motivation. Also by studying animals at various ages, information will be obtained regarding the maturation of the visual processing system.